1. Field of the Invention
The present invention relates to a fixing device for a shield can for shielding electromagnetic waves generated in electronic function groups placed on a printed circuit board of various electronic devices. More particularly, the present invention relates to a fixing device for a shield can capable of contributing improvement of product reliability while providing an advantage in terms of workability, maintenance, and space utilization.
2. Description of the Related Art
In general, various electronic devices or communication devices provide a variety of contents, and include a printed circuit board to electrically connect their contents. When using the electronic devices or the communication devices, various electronic function groups placed on the printed circuit board may produce harmful electromagnetic waves. Therefore, the electromagnetic waves produced in the various electronic devices are strictly regulated.
For example, an environmental compatibility test is used to test whether the harmful electromagnetic waves are suitable for an environment, that is, to test ElectroMagnetic Compatibility (EMC).
The EMC is classified into two types, i.e., ElectroMagnetic Interference (EMI) and ElectroMagnetic Susceptability (EMS), each of which is strictly regulated since it can harm the human body. Therefore, many devices have been proposed to avoid exposure to the electromagnetic waves in advance by strict regulation of the EMC test.
For example, in order to shield electromagnetic waves produced in respective elements placed on a printed circuit board used in a portable terminal, a coating may be applied by using EMI spread or vacuum evaporation, or a shield can may be placed on the printed circuit board.
The aforementioned methods are generally used in combination, and the shield can is necessarily configured. In particular, various methods of placing the shield can on the printed circuit board are known. Examples of these methods include a mechanical combining method, a clip-type combining method, a frame-type combining method, etc.
The mechanical combining method combines the shield can to the printed circuit board by using a plurality of screws, and has advantages in terms of maintenance, but also has disadvantages in terms of product reliability such as screw deviation due to long-term use.
The clip-type combining method first places a clip on the printed circuit board along an outer edge of the shield can, and then fixes the shield can to the clip. This method has advantages in terms of maintenance and manufacturing costs, but also has disadvantages in terms of reliability, such as deviation of the shield can from the clip due to even a slight impact.
The frame-type combining method installs an additional frame by enclosing electronic function groups on the printed circuit board and fixes the shield can to the frame. Although reliability is excellent, it is difficult to apply this method to a slim-type product since a large area is used on the printed circuit board.